Patent · US Expired

Helicopter rotor blades

US5199851A · kind A · utility

11Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1991
Grant dateApr 6, 1993
Priority date
Expiry dateOct 23, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T50/10
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A helicoper rotor blade includes at its outer end a tip vane having a mean chord length greater than fifty percent of a chord length of a blade central portion and a span length greater than fifty percent of the blade chord which in operation generates two approximately equal strength tip vortices to reduce an acoustic impulse and a resulting noise known as blade slap.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.